Conventionally, circuit assemblies are known in which an insulating board which has conductive paths formed thereon and to which busbars are bonded is placed on a heat dissipation member. In a circuit assembly disclosed in JP 2005-15167A, a circuit member formed by bonding a plurality of busbars to a control circuit board and mounting electronic components thereon is bonded on top of a heat dissipation member.
Control circuit boards such as that disclosed in JP 2005-15167A are generally formed to have a small thickness. Therefore, a circuit member in which busbars are bonded to such a control circuit board has low stiffness and is prone to deformation, and there are problems in that handling is not easy, and a gap will be formed between the circuit member and the heat dissipation member due to deformation of the circuit member and cause a decrease in heat dissipation properties. Moreover, the JP 2005-15167A discloses, during fixation of the circuit member to the heat dissipation member, the circuit member is pressed against the heat dissipation member. There is a problem in that when the circuit member is pressed against the heat dissipation member, if the pressure applied to the adhesive via the circuit member is nonuniform, the adhesion of the adhesive will be insufficient depending on the location, resulting in a decrease in heat dissipation properties.